Step-by-step explanation:
5a+4a=180
a=20
5a=X
X=5×20
=100°
Answer:
100 degrees
The opposite angle will always be the same. since the opposite is 5a, then x = 5a. x is 5a, and 9a is 180 degrees so x=180(5/9), which is equal to 100 degrees.
